I was searching in stackoverflow and the web, could not get proper results or explanation siting difference between these three methods.
As far as i understand, the
apply
and call
are the same thing except one accepts the arguments to be passed to the function in array form the other in parameter form.
bind
does the same thing as call
or apply
depending on the framework you are using but doesn't call the function right away instead it returns a new function with your parameters bound to this
and when the function is called from a new scope or context, this
will still remain whatever you bound to it. Binding also allows you to prevent your constructors from being "hacked" by apply
or call
since it will always use the binded parameters for this
no matter what someone sends to attempt to override this
via call
or apply
.
Here is an example:
function Profile(u) {
this.user = u;
this.getUser = function () {
return this.user;
};
}
function Profile2(u) {
this.user = u;
this.getUser = (function () {
return this.user;
});
}
function Profile3(u) {
this.user = u;
this.getUser = (function () {
return this.user;
});
}
var x = new Profile('guest');
var x2 = new Profile2('guest');
var x3 = new Profile3('guest');
alert(x.getUser.apply({
user: 'Vinoth'
})); // Vinoth
alert(x2.getUser.call({
user: 'Babu'
})); // babu
alert(x3.getUser.bind(x3).call({
user: 'Nandan'
})); // Guest